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Wyniki wyszukiwania dla: rivers , snow , synthetic aperture radar , time series analysis , fault location , backscatter
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On Bayesian Tracking and Prediction of Radar Cross Section
PublikacjaWe consider the problem of Bayesian tracking of radar cross section. The adopted observation model employs the gamma family, which covers all Swerling cases in a unified framework. State dynamics are modeled using a nonstationary autoregressive gamma process. The principal component of the proposed solution is a nontrivial gamma approximation, applied during the time update recursion. The superior performance of the proposed approach...
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Forecasting energy consumption and carbon dioxide emission of Vietnam by prognostic models based on explainable machine learning and time series
PublikacjaThis study assessed the usefulness of algorithms in estimating energy consumption and carbon dioxide emissions in Viet- nam, in which the training dataset was used to train the models linear regression, random forest, XGBoost, and AdaBoost, allowing them to comprehend the patterns and relationships between population, GDP, and carbon dioxide emissions, energy consumption. The results revealed that random forest, XGBoost, and AdaBoost...
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Seasonal and spatial differences in metal and metalloid concentrations in the snow cover of Hansbreen, Svalbard
PublikacjaMetals and metalloids in snow on glaciers, depending on the season of deposition, may come from various sources: local rock dust (erosion of the geological substratum), marine aerosol, local human activity (e.g. fuel combustion, waste incineration) and long-range atmospheric transport. Hansbreen glacier, located close to the Polish Polar Station in Svalbard, is a perfect site to study metals and metalloids: it has complex geological...
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Acoustic radar employing particle velocity sensors
PublikacjaA concept, practical realization and applications of a passive acoustic radar to automatic localization, tracking of sound sources were presented in the paper. The device consist of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surroundings sounds it provide information about the...
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THE CONCEPT OF MODELING OF SNOW IMPACT ON THE STRUCTURE OF THE SUSPENDED TAURON ARENA ROOF IN CRACOW
PublikacjaThe article presents studies and numerical simulations on modeling snow influence on TAURON ARENA suspended roof structure in Cracow. The scope of work includes experimental tests, functions solutions taking into account various cases of snow impact according to PN and EC, as well as numerical simulations for the sport and entertainment arena in the Czyzyny district. The FEM roof structure model developed in the SOFISITK software...
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Errors in the analysis of series resonant inverter/converter assuming sinusoidal waveforms of voltage and current
PublikacjaIn this paper the theory and simulation results of the series resonant inverter / converter are presented. In this work the authors carried out a detailed comparative analysis of results obtained using the method of AC analysis in the steady state for the first harmonic with the results of computer simulation. The AC analysis under certain conditions can lead to errors disqualifying this method. In particular, these errors appear...
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Emulator and simulator of Terma SCANTER and ARPA radar data server
PublikacjaThe software solutions presented in this paper generate real-time data compatible with ARPA radar standard as well as Terma SCANTER 2001 radar cooperating with Video Distribution and Tracking (VDT) server. Two different approaches to this problem are considered: emulation based on the data captured from real devices and simulation of objects on the sea. For both of them architecture, implementation details and functional test results...
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PCA based Fault Tolerant MPC
PublikacjaThis chapter presents a Fault Tolerant - Model Predictive Control (FT-MPC) schemes for sensor faults accommodation. A Fault Detection and Isolation (FDI) Unit, which is an integral part of FT-MPC system, is based on the Principal Component Analysis (PCA) method. Introduced approach enables efficient bias and drift faults accommodation in single, as well as simultaneous faults case. Simple simulation exercise is presented.Rozdział...
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Adaptation of radar software to work with ambiguous distance measurement
PublikacjaA software extension for radar stations designed to work in the low-PRF mode that allows them to correctly measure range to targets outside of their instrumented range, is proposed. The solution does not require substantial modifications of the radar software. Additionally, we describe tools that allow one to simulate the output of a low-PRF radar observing targets that are outside its instrumented range. The proposed approach...
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Hyperbolic position location estimation in the multipath propagation environment
PublikacjaThe efficiency analysis a hyperbolic position location estimation in the multipath propagation environment in the wideband code division multiple access (WCDMA) interface was presented. Four, the most popular methods: Chan's, Foy's, Fang's and Friedlander's were considered. These algorithms enable the calculation of the geographical position of a mobile station (MS) using the time differences of arrival (TDOA) between several base...
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Low Cost Method for Location Service in the WCDMA System
PublikacjaA new and low cost method for a location service (LCS) in the Wideband Code Division Multiple Access (WCDMA) system is outlined. This method, which is called TDOA + RTT, enables calculation of the geographical position of a mobile station (MS) without knowledge of relative time differences (RTDs) between base stations (BSs). The TDOA+RTT method is based on the measurement of round trip times (RTTs) between the MS and the serving...
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Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018
PublikacjaLight-absorbing carbonaceous aerosols emitted by biomass or fossil fuel combustion can contribute to amplifying Arctic climate warming by lowering the albedo of snow. The Svalbard archipelago, being near to Europe and Russia, is particularly affected by these pollutants, and improved knowledge of their distribution in snow is needed to assess their impact. Here we present and synthesize new data obtained on Svalbard between 2007...
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Detection and time/frequency analysis of electric fields in the ground
PublikacjaThis paper sets out to detect and characterize electric fields in the ground (such as stray current fields) using a tandem time/frequency method of signal analysis. Results were obtained from investigations performed in the presence of a generated electric field with controlled variable characteristics, and in the presence of an electric field generated by a tramline. The analysis of measurement registers was performed using Short‐Time...
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A novel heterogeneous model of concrete for numerical modelling of ground penetrating radar
PublikacjaThe ground penetrating radar (GPR) method has increasingly been applied in the non-destructive testing of reinforced concrete structures. The most common approach to the modelling of radar waves is to consider concrete as a homogeneous material. This paper proposes a novel, heterogeneous, numerical model of concrete for exhaustive interpretation of GPR data. An algorithm for determining the substitute values of the material constants...
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A fast time-frequency multi-window analysis using a tuning directional kernel
PublikacjaIn this paper, a novel approach for time-frequency analysis and detection, based on the chirplet transform and dedicated to non-stationary as well as multi-component signals, is presented. Its main purpose is the estimation of spectral energy, instantaneous frequency (IF), spectral delay (SD), and chirp rate (CR) with a high time-frequency resolution (separation ability) achieved by adaptive fitting of the transform kernel. We...
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Static Series and Shunt-series PE Voltage-quality Controllers
PublikacjaAs presented in the Chap. 7 static shunt power electronics (PE) voltage-quality controllers protect the utility electrical system from the unfavorable impact of customer loads. Shunt controllers, as shown in Chap. 6, are recommended mainly for mitigation of the causes of disturbances, and not their effects in distanced nodes of a power-electronics system. In the case when reduction of disturbances effects is required, which leads...
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Accuracy analysis of the radio location service in the sea environment
PublikacjaW artykule przedstawiono koncepcję systemu bezpieczeństwa na morzu w oparciu o istniejące systemy komórkowe. Scharakteryzowano problem lokalizowania terminala ruchomego przez sieć w warunkach morskich. Przedstawiono wyniki badań przeprowadzonych w warunkach rzeczywistych w odniesieniu do efektywności lokalizowania terminala na morzu. Przedstawiono wnioski, wypływające z przeprowadzonych analiz.
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Accuracy analysis of a mobile station location in the cellular networks
PublikacjaJakość usług lokalizacyjnych oferowanych w sieciach komórkowych zależy od efektywności estymacji położenia terminala ruchomego. Dokładność obecnie stosowanych metod lokalizacyjnych jest niewystarczająca, szczególnie w odniesieniu do wywołań w niebezpieczeństwie. Modyfikacja istniejących algorytmów może istotnie wpłynąć na zwiększenie dokładności lokalizowania terminala ruchomego przy jednocześnie niewielkich nakładach finansowych....
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VISUALIZATION OF SCANTER AND ARPA RADAR DATA IN THE DISTRIBUTED TELEINFORMATION SYSTEM FOR THE BORDER GUARD
PublikacjaMonitoring of country maritime border is an important task of the Border Guard. This activity can be enhanced with the use of the technology enabling gathering information from distributed sources, processing of that information and its visualization. The paper presents the next stage of development of the STRADAR project (Streaming of real-time data transmission in distributed dispatching and teleinformation systems of the Border...
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Water hammer analysis in two pipes in series
PublikacjaW pracy przedstawiono wyniki badań laboratoryjnych przepływu nieustalonego w rurociągu skokowo zmiennej średnicy. Dokonano porównania czynników pomiarów oraz obliczeń uderzenia hydraulicznego zmodyfikowaną metodą elementów skończonych.
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The Snow Team Problem
PublikacjaWe study several problems of clearing subgraphs by mobile agents in digraphs. The agents can move only along directed walks of a digraph and, depending on the variant, their initial positions may be pre-specified. In general, for a given subset~$\cS$ of vertices of a digraph $D$ and a positive integer $k$, the objective is to determine whether there is a subgraph $H=(\cV_H,\cA_H)$ of $D$ such that (a) $\cS \subseteq \cV_H$, (b)...
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Efficient Calibration of Cost-Efficient Particulate Matter Sensors Using Machine Learning and Time-Series Alignment
PublikacjaAtmospheric particulate matter (PM) poses a significant threat to human health, infiltrating the lungs and brain and leading to severe issues such as heart and lung diseases, cancer, and premature death. The main sources of PM pollution are vehicular and industrial emissions, construction and agricultural activities, and natural phenomena such as wildfires. Research underscores the absence of a safe threshold for particulate exposure,...
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Mechanical Strength of MV Ship-switchgear During Fault Arc
PublikacjaIn the paper the analysis of pressure stressed in enclosure during fault arc inside switchgear is pre-sented as well. There is introduced the method based on determining stresses which are sum of tensile stresses (membrane) and deflection stresses. For tensile stresses nalysis the energy method, for unrestrainedly supported rectangular plate, was used. In the further part of the paper, the calculations and measurements results...
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Estimating Traffic Intensity Employing Passive Acoustic Radar and Enhanced Microwave Doppler Radar Sensor
PublikacjaInnovative road signs that can autonomously display the speed limit in cases where the trac situation requires it are under development. The autonomous road sign contains many types of sensors, of which the subject of interest in this article is the Doppler sensor that we have improved and the constructed and calibrated acoustic probe. An algorithm for performing vehicle detection and tracking, as well as vehicle speed measurement,...
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Asynchronous phase-location system
PublikacjaThis paper presents concept and implementation of digital phase-location system, designed as a navigational aid for marine applications. The main feature of the proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronised with master, and in asynchronous mode with independent clocking of all stations.
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A Clustering-Based Methodology for Selection of Fault Tolerance Techniques
PublikacjaDevelopment of dependable applications requires selection of appropriate fault tolerance techniques that balance efficiency in fault handling and resulting consequences, such as increased development cost or performance degradation. This paper describes an advisory system that recommends fault tolerance techniques considering specified development and runtime application attributes. In the selection process, we use the K-means...
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Analysis of beam sharpening effectiveness in broadband radar on inland waters
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Determination of pharmaceuticals in fish: method optimization and occurrence in different species from Mediterranean rivers
PublikacjaThe multi-residue analytical method developed, based on accelerated solvent extraction, gel permeation chromatography purification and UPLC-MS/MS analysis allowed the simultaneous determination of 21 pharmaceuticals. Recoveries obtained for most of the target compounds were higher than 50%. The application of UPLC-MS/MS operating in the MRM mode, with two transitions monitored for each compound, provided good sensitivity and selectivity....
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Training of Deep Learning Models Using Synthetic Datasets
PublikacjaIn order to solve increasingly complex problems, the complexity of Deep Neural Networks also needs to be constantly increased, and therefore training such networks requires more and more data. Unfortunately, obtaining such massive real world training data to optimize neural networks parameters is a challenging and time-consuming task. To solve this problem, we propose an easy-touse and general approach to training deep learning...
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Machine-learning-based precise cost-efficient NO2 sensor calibration by means of time series matching and global data pre-processing
PublikacjaAir pollution remains a considerable contemporary challenge affecting life quality, the environment, and economic well-being. It encompasses an array of pollutants—gases, particulate matter, biological molecules—emanating from sources such as vehicle emissions, industrial activities, agriculture, and natural occurrences. Nitrogen dioxide (NO2), a harmful gas, is particularly abundant in densely populated urban areas. Given its...
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Faults and Fault Detection Methods in Electric Drives
PublikacjaThe chapter presents a review of faults and fault detection methods in electric drives. Typical faults are presented that arises for the induction motor, which is valued in the industry for its robust construction and cost-effective production. Moreover, a summary is presented of detectable faults in conjunction with the required physical information that allow a detection of specific faults. In order to address faults of a complete...
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A concept of software extension of 3D low-PRF radar systems to 4D semi-medium-PRF radar systems
PublikacjaWe present a concept of software modification of three-dimensional (3D) radar systems, designed to work in the low pulse repetition frequency mode, that equips them with the ability to estimate the radial velocity and to properly measure the range of targets that are detected outside the radar’s instrumented range. Despite the fact that the proposed modifications are designed so as to require only minor changes in software, they...
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Possibility of Fault Detection in Sensorless Electric Drives
PublikacjaThe work presents a fault detection method for an induction motor drive system with inverter output filter. This approach make use of a load torque state observer, which complete structure is presented along with the used control structure. Moreover, the demonstrated drive system operates without rotor speed measurement in conjunction with the multiscalar control. The verification of the demonstrated idea was performed on an experimental...
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Application of time-series-cross-section data in case of sale forecasting in an enterprise
PublikacjaW artykule wskazano możliwości wykorzystania danych przestrzenno-czasowych do prognozowania sprzedaży w przedsiębiorstwie. Przedstawiono różne podejścia do prognozowania ekonometrycznego przy użyciu tego typu danych. Wyznaczono krótkookresowe prognozy sprzedaży benzyny bezołowiowej Pb95 w przekroju województw oraz dokonano oceny ich jakości przy użyciu mierników ex-post. Dwie najdokładniejsze metody prognozowania wykorzystano do...
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Autocovariance based weighting strategy for time series prediction with weighted LS-SVM
PublikacjaPrzedstawiono metodę konstrukcji algorytmów z funkcją jądra, a także dwa algorytmy uzyskane poprzez użycie różnych funkcji straty. Zaproponowano kowariacyjną strategię ważenia algorytmów z kwadratową funkcją straty do problemu predykcji chaotycznych przebiegów czasowych.
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Spatiotemporal Assessment of Satellite Image Time Series for Land Cover Classification Using Deep Learning Techniques: A Case Study of Reunion Island, France
PublikacjaCurrent Earth observation systems generate massive amounts of satellite image time series to keep track of geographical areas over time to monitor and identify environmental and climate change. Efficiently analyzing such data remains an unresolved issue in remote sensing. In classifying land cover, utilizing SITS rather than one image might benefit differentiating across classes because of their varied temporal patterns. The aim...
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Risk of Delays in Implementation of Building Investment in Urban Conditions in the Aspect of Historical Background of its Location
PublikacjaThe implementation of a construction investment in urban conditions is extremely complex, and at the same time exposed to a high risk of a specific character. In case of construction investment located in the historic part of the city, the possible accumulation of many unfavourable factors, which in course of its implementation, may constitute a serious source of delays and disruptions, should be taken into account at the preparation...
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Detection of broadband signals in the field of aperture and array systems.
PublikacjaAnteny i szyki anten w dolnopasmowych systemach hydroakustycznych wnoszą istotne zniekształcenia liniowe wpływające na możliwości detekcji sygnałów szerokopasmowych. W artykule analizowany jest charakter takich zniekształceń metodą przestrzenno - czasowych odpowiedzi impulsowych. Sygnał odbierany w różnych kierunkach przestrzeni poddano filtracji na dwa sposoby z filtrem dopasowanym do sygnału nadawanego i filtrem dopasowanym...
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A novel method of time-frequency analysis: an essential spectrogram
PublikacjaA novel precise method of time-frequency analysis is presented. In the algorithm, a new energy distribution is estimated by simultaneously discard or displacement of the classical spec- trogram energy. A channelized instantaneous frequency and a local group delay are used in order to replacement in the same manner as formulated by Kodera et al. [1, 2]. Additionally, new representations: a channelized instantaneous bandwidth and...
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The Effect of Valley Location in Two-Process Surface Topography Analysis
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Nonlinear Modeling in Time Domain Numerical Analysis of Stringed Instrument Dynamics
PublikacjaMusical instruments are very various in terms of sound quality with their timbre shaped by materials and geometry. Materials' impact is commonly treated as dominant one by musicians, while it is unclear whether it is true or not. The research proposed in the study focuses on determining influence of both these factors on sound quality based on their impact on harmonic composition. Numerical approach has been chosen to allowed independent...
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COMPLEXITY OF INNOVATIVE FINANCIAL PRODUCTS: THE CASE OF SYNTHETIC EXCHANGE TRADED FUNDS IN EUROPE
PublikacjaThe aim of the text is the presentation of the most important categories of exchange traded funds (ETFs) – physical and synthetic ones. A theoretical part of the text includes an overview of the main features of ETFs, the presentation of differences between physical and synthetic funds and the main risks posed by both types to their users and the whole financial systems. An empirical part focuses on the European market. Time span...
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Time-frequency analysis of acoustic signals using concentrated spectrogram
PublikacjaThe paper presents improved method of time-frequency (TF) analysis of discrete-time signals. The method involves signal's local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute all Short-time Fourier transform (STFT) lines. Additionally, the energy concentration index (ECI) and some histogram-like statistics are used to evaluate readability of estimated TF distributions of the energy. Recorded...
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Algoritmically improved microwave radar monitors breathing more acurrate than sensorized belt
PublikacjaThis paper describes a novel way to measure, process, analyze, and compare respiratory signals acquired by two types of devices: a wearable sensorized belt and a microwave radar-based sensor. Both devices provide breathing rate readouts. First, the background research is presented. Then, the underlying principles and working parameters of the microwave radar-based sensor, a contactless device for monitoring breathing, are described....
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Novel Fault Identification for Electromechanical Systems via Spectral Technique and Electrical Data Processing
PublikacjaIt is proposed, developed, investigated, and validated by experiments and modelling for the first time in worldwide terms new data processing technologies, higher order spectral multiple correlation technologies for fault identification for electromechanical systems via electrical data processing. Investigation of the higher order spectral triple correlation technology via modelling has shown that the proposed data processing technology...
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High resolution liquid chromatography and time of flight mass spectrometry in perfume analysis
PublikacjaPerfumes consist of a wide range of natural and synthetic compounds that belongs to different chemical classes. Most of these compounds are generally determined by GC. However, in this study RP-HPLC-Q-TOF-MS and HILIC-Q-TOF-MS technique was applied for the determination of ingredients of original perfumes and their imitations. Antioxidants and compounds specific to fragrances of animal \origin were found in original...
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Facile synthetic route to selectively protected spermidine homologues
PublikacjaW wyniku opracowanej procedury otrzymano kilka selektywnie chronionych homologów spermidyny. Reakcja cyjanoetylowania monochronionych diamin pozwoliła na otrzymanie nitryli, które przekształcano w amidy pierwszorzędowe. Degradacja Hofmanna amidów doprowadziła do otrzymania finalnych związków.
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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
PublikacjaDue to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed:...
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Selecting the optimum location for logistics facilities using Solver
PublikacjaSiting logistics facilities strategically in the most costeffective geographic location is one of the key decisions a contemporary company will make. The aim of the paper is to present a solution to this problem using the Solver add-on. In the case study discussed in the paper, the company’s central warehouse location was selected based on the classic location theory, which addresses the need to minimize the cost of transport....
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Energy Efficiency Analysis of Railway Turnout Heating With a Simplified Snow Model Using Classical and Contactless Heating Method
PublikacjaElectrical heating of railway turnouts is a considerable technical and economic challenge, hence the need to conduct research for optimisation of a railway turnouts heating system. This paper presents results of a numerical analysis and experimental research on heating systems mounted on rail turnouts in line with the classical method and including a heater thermally insulated from the base of a rail. The numerical calculations...